The present invention relates generally to the field of recorders.
Previously, for a recorder to record or replay music, the recorder would detect the operating conditions of numerous switches of an operator and then run a process in response to those operating conditions. The operating conditions of the switch are detected from the scanning intervals. See Japanese Published Unexamined Application 2004-348921.
However, in previous recorders, the scan is run at a set interval and the scan creates noise. When the noise is recorded or replayed with the input musical sound, a problem of abrasive and jarring noise arises. For example, when the scan interval is 5 milliseconds, the noise level is at a frequency of 200 Hz, creating an abrasive noise. Consequently, when the scan interval is 50 milliseconds, the noise level frequency becomes 20 Hz, which is lower than the frequency audible to humans, does not create an abrasive noise. When the automatic performance data, such as a rhythm pattern, is created to perform in real time, if proper timing is not detected, the intended performance cannot be replayed.
As various processes are run with control equipment such as a Central Processing Unit (CPU), when the operating conditions of the switch are detected, and the scan interval for the switch is fast, processing occurs slower. When the processing slows down, a problem of not being able to properly detect the switch operations may occur.
Embodiments of the present invention relate to solutions to the above problems and allow the switch scan of the recorder to run at an appropriate interval.